1. Field of the Invention
This invention is concerned with the field of edge trimmers and more particularly with a swivel wheel device attached to a trimmer to allow 360 degree swiveling.
2. Description of Prior Art
The prior art contains references to edgers that are equipped with wheels; however, an edger is totally different than a trimmer. As taught in U.S. Pat. No. 6,263,975, an edger has a rotating blade for edging around cement. A trimmer is a device also sometimes called a weed eater. A trimmer generally has a rotating flying cutting string or strings (which may be fish line or other strong string-like material). The rotating string slices weeds and grass to perform the edging or weeding function.
A great disadvantage of the flying string trimmer is that it is hard to keep it at a certain fixed level above the desired cutting surface. Another disadvantage is that because the height is hard to control, the string wears out faster because the unit cuts deeper and digs rocks, etc.
What is badly needed is a removable device for a trimmer that maintains a controllable height and allows the trimmer to swivel 360 degrees and forms a fulcrum for a lever arm so that the trimmer can be raised or lowered toward the target cutting surface.
The present invention presents an apparatus and method that allows a conventional trimmer of the type with flying cutting string to maintain a controllable height above the cutting plane and to swivel 360 degrees. The present invention includes a set of wheels that also acts as a fulcrum point forming a lever with the heavier head of the trimmer closer to the wheels and the handle acting as a long lever arm. The tool also can be rotated backward with the cutting end up for service with the entire system in a stable resting position.
The present invention allows an operator to trim around curbs and edges without making contact. It conserves string and is safer because it picks up less trash and rocks. The present invention also leads to smoother cutting because the cutting plane is accurately defined and can be controlled. The present invention converts any standard trimmer into a mini-lawnmower allowing less strain on the operator in using it (it is held off the cutting plane or ground by the wheels rather than the operator). The present invention allows a standard trimmer to be used without a shoulder strap if desired (a shoulder strap can of course be used if desired).
The present invention consists of a set of swivel wheels (at least two wheels) attached to the long handle of a standard trimmer (while more than two wheels could be used, the preferred method is to use two wheels). The wheels are castered so that they can rotate 360 degrees.
The preferred means of attaching the wheels to the trimmer handle is through a series of two clamps (although one clamp is within the scope of the present invention, it does not result in as stable a system as that with two or more clamps). The preferred size of the wheels is around one inch thick and about four inches in diameter; however, it should be realized by those skilled in the art that many other sizes of wheels could be used with equal success. The preferred distance between the wheels is about 22 inches; however, many other distances are possible. If the distance between the wheels is too small, the device becomes unstable and could fall over sideways. If the distance is too large, the device becomes cumbersome to use and will not turn on a tight radius.
The preferred configuration consists of a lower clamp and an upper clamp on the long tubular handle of the trimmer. The two clamps can be separated from one another from 6 to over 20 inches with about equal results. The wheels can be attached to the lower clamp through two strut-like structures (which can be aluminum tubing or other rigid material) forming a V or U shape with the wider legs of the V or U at the bottom. To give the structure fore and aft support, a pair of support tubes can extend downward to the wheels from the upper clamp. The lower struts can form an arc as well as a V (or any other convenient and strong configuration).
The preferred height for the lower clamp to the ground is about 12 inches although many other heights are within the scope of the present invention. The key idea is to create a lever out of the trimmer with the fulcrum point at the lower clamp. The entire system can that be levered fore and aft to define a cutting height. As stated, the system can also be levered completely backward (so the motor drive is on the ground) to raise the cutting head upward for service or string replacement.
It is also possible to mount an optional handle-bar structure on a third clamp above the other two to make it easier to steer and control the apparatus. The entire apparatus thus can be put into two rest positions with the trimmer motor off. If the apparatus is allowed to lever forward, the cutter head will touch the ground and support the apparatus in an upright position. If the apparatus is tilted backward, because of the weight of the motor on the top end, it will sit in a stable rest position with the motor on the ground and the cutting head sticking approximately straight out as stated, this position is very convenient to service the head including the installation of a new string.